CN1885859B - Method for supporting combined circuit domain call and Internet multimedia subsystem dialogue - Google Patents

Abstract

A method for supporting a combined circuit domain call and Internet multimedia subsystem dialogue, comprising the following steps: a CS domain call is established between user A and user B; the terminal of user A obtains the capabilities and IP addresses of all terminals of user B; The terminal of user B obtains the capabilities and IP addresses of all terminals of user A; the party that initiates the CSI service carries the called IP address in the invitation message, and the called serving call session control function (S-CSCF) sends the invitation message only Send to the terminal matching the IP address. Through the present invention, both parties making a CS domain call can obtain all terminal capabilities and IP addresses of the opposite end user, thereby effectively performing CSI services and enhancing user experience.

Description

Method for supporting combined circuit domain call and Internet multimedia subsystem dialogue

technical field

The present invention relates to the third generation of mobile communication, in particular to the ability exchange of combined circuit domain call and Internet multimedia subsystem dialogue.

Background technique

Internet Multimedia Subsystem (hereinafter referred to as IMS) is a structural framework formulated by 3GPP to provide users with Internet multimedia services (see Figure 1 for details). Before the user utilizes IMS to conduct business, he must first register with the Serving Call Session Control Function (hereinafter referred to as S-CSCF) in the IMS. This registration is to inform the S-CSCF of the user's public user identity (hereinafter referred to as PUI) The binding relationship of the IP address of the location. Of course, during the registration process, the user can also tell the network some of his features, supported capabilities, etc. For details, please refer to the 3GPP specification TS 23.228. The Proxy Call Session Control Function (hereinafter referred to as P-CSCF) in Figure 1 is a proxy gateway used to access the IMS. It is usually a gateway of the network where the user is currently located. The time is notified by the network through the P-CSCF discovery. For specific steps, please refer to TS23.228. The P-CSCF finds an Inquiry Call Session Control Function (hereinafter referred to as I-CSCF) by analyzing the home network domain name included in the user's PUI, and knows the user's identity through the interaction between the I-CSCF and the home network registration subscriber server (hereinafter referred to as HSS). The S-CSCF. After the I-CSCF finds the user's S-CSCF, it forwards the message received from the P-CSCF to the S-CSCF for processing by the S-CSCF. If the S-CSCF has not stored the service attributes of the user, it will request such information from the HSS. S-CSCF continues to process messages received from users.

The message between the UE and the P-CSCF in the IMS system uses the Session Initiation Protocol (hereinafter referred to as SIP). The SIP message in the IMS system follows the request principle and response principle defined in RFC 3261 for invitation INVITE, registration REGISTER, option OPTIONS and other messages. The routing of messages in the IMS system is particularly important. There is a field called Request-URI in the header of each SIP message. The originating S-CSCF finds the called S-CSCF through this field. In the IMS system, the Request-URI field is usually identified by the user's PUI. The PUI can be a SIP URI expressed in the form of email, or a TEL URI expressed in the form of a phone number. If the TEL URI is used, then when the calling S-CSCF receives the identifier, it will be converted into a standard SIPURI through ENUM DNS (refer to RFC 2916 of IETF). Then when the calling S-CSCF sends a message to the called S-CSCF, it uses the SIP URI to identify the user.

According to the foregoing, when each user registers, it will inform its S-CSCF of the mapping relationship between its PUI and IP address. In the IMS system, the same user may have one or more terminal equipments, ie UEs. The multiple terminal devices may bind the same PUI to different IP addresses of each terminal when registering with the network.

When the called S-CSCF prepares to send a SIP message to a certain user identified by PUI, since the SIP message is encapsulated in an IP packet, the S-CSCF needs to distinguish which terminal device the message should be sent to. If multiple terminals use one PUI for user identification, then the S-CSCF will send the same SIP message to these multiple terminal devices. Of course, the request URI in the SIP message uses the IP address registered by each terminal.

On the basis of IMS, 3GPP is formulating a combined circuit domain call and IMS session (hereinafter referred to as CSI) standard, as shown in FIG. 8 . There are two clients in one user equipment, one is a call for circuit domain (hereinafter referred to as CS domain), and the other is a session for IMS domain. When a CS domain call and an IMS domain session are simultaneously performed between the same two UEs, the same combined service is presented to the user at the application layer of the user equipment. In this way, some interactions and operations between the CS domain and the IMS domain are required. The CS core in FIG. 8 refers to the collective name of network entities involved in CS domain calls, generally including mobile terminal interaction center (hereinafter referred to as MSC), visitor location register (hereinafter referred to as VLR) and so on. The IMS core refers to the collective name of the network entities involved in the IMS domain session, and generally includes all the entities in FIG. 1 .

Before the two UEs perform the CSI service, the two UEs must know the user's ability to support CSI in advance. The user's ability to support CSI is passed through the OPTIONS message. Figure 2 describes the ability of the terminal to be transferred between two users through the OPTIONS message. The parameters included in the message include user A's MS-ISDN, SIP URI, media bearer type, whether to support CSI, and so on. For specific parameters, please refer to 3GPP TS 23.279. Then, the 200 OK message sent by UE B to UE A includes user B's MS-ISDN, SIP URI, media bearer type, whether to support CSI, and so on. In this way, UE A knows the terminal capability of UE B, and UE B also knows the terminal capability of UE A. The terminal capability of the opposite end is stored in the user terminal and monitored by a timer. If the timer expires, the new terminal capability exchange process will be restarted, and the peer terminal capability stored in the memory will be overwritten by the new terminal capability.

What Fig. 3 explains is the problem existing in the prior art.

When the same PUI of a user is bound to multiple terminal devices, the user's S-CSCF will send the same message, namely 303 and 304, to the multiple terminal devices. When exchanging terminal capabilities in CSI, the OPTIONS message will be sent to multiple terminals. Generally speaking, when the called party receives the OPTIONS message, it will return a 200 OK message to the initiator. When the called S-CSCF receives the first 200OK 305, it forwards the message to the calling S-CSCF, and then routes it back to the calling user equipment.

For a user on one side, when he wants to initiate a CSI service, all he cares about is that he can use the same terminal to add an IMS session on the basis of a call in the CS domain, and he does not care whether the merged service at the other end occurs in a On the terminal, or on two terminals. Therefore, it is required that the terminal in progress of the session should save the capabilities of all the terminals of the peer user. But existing technology can't realize.

Contents of the invention

In order to solve the above problems, the object of the present invention is to provide a method for supporting combined circuit domain calls and Internet t multimedia subsystem calls, which can realize the ability of the two terminals that are calling to save all terminals of the opposite end user.

In order to achieve the above object, a method for supporting a combined CS domain call and Internet multimedia subsystem dialogue includes the following steps:

a) A CS domain call is established between user A and user B;

b) The terminal of user A obtains the capabilities and IP addresses of all terminals of user B;

c) The terminal of user B obtains the capabilities and IP addresses of all terminals of user A;

d) The party that initiates the CSI service carries the IP address of the called party in the invitation message, and the called Serving Call Session Control Function (S-CSCF) sends the invitation message only to terminals that match the IP address.

Through the present invention, both parties making a CS domain call can obtain all terminal capabilities and IP addresses of the opposite end user, thereby effectively performing CSI services and enhancing user experience.

Description of drawings

Figure 1 is a block diagram of the IMS architecture;

FIG. 2 is a schematic diagram of UE using OPTIONS to exchange terminal capabilities;

Fig. 3 is the schematic diagram of prior art;

FIG. 4 is Embodiment 1 of exchanging terminal capabilities;

FIG. 5 is a second embodiment of exchanging terminal capabilities;

Fig. 6 is the embodiment of initiating a session;

Figure 7 is a schematic diagram of the composition of the invention;

Figure 8 is the framework of the CSI structure.

Detailed ways

Fig. 7 is the inventive structure of the present invention.

After a CS domain call has been established between two users 701, the terminal of user A obtains the capabilities and IP addresses of all terminals of user B 702, and the terminal of user B also obtains the capabilities and IP addresses of all terminals of user A 703 .704 When user A or user B wants to join the IMS session, the IP address of the called terminal should be included in the invitation message sent. The S-CSCF at the called end shall send the invitation message only to the terminal equipment whose registered address is the IP address of the called party.

Figure 4 is an embodiment of the present invention.

Before user A and user B initiate a capability exchange request, a CS domain call has been established between UE A1 and UE B1. User A knows the MS-ISDN number corresponding to user B's UE B1 terminal.

When the terminal UE A1 of the initiator of capability exchange initiates the process of terminal capability exchange, it sends a 401 TRANSFER message to S-CSCF A, which contains the TEL URI composed of UE B1's MS-ISDN number, or user B's SIP URI, if and only if the corresponding relationship between the TEL-URI and the SIP URI of user B is stored in UE A1. If the 401 message contains the TEL URI, S-CSCF A replaces the TEL URI in the message with the SIP URI of user B, and then sends the message to S-CSCF B. How S-CSCF A knows the SIP URI of user B and how to find S-CSCFB of user B is not within the scope of the present invention, please refer to the prior art. In this embodiment, it is assumed that user B has two terminals UE B1 and UE B2, and both terminals have registered with S-CSCFB with the same SIP URI. So S-CSCF B sends the transmission message to UE B1 and UE B2. After UE B1 and UE B2 include their own terminal capabilities in the 200OK message, they send this message to S-CSCFB. S-CSCF B is responsible for forwarding these two responses to UE A1. In this way, UE A1 retains the terminal capabilities of UE B1 and UE B2. The transmission messages of 405 and 408 may also include the contact IP addresses of UE B1 and UE B2, so that UE A1 can store these two IP addresses and the corresponding SIP URI. When user A wants to join the IMS session with user B through UE A1, the invitation message sent by UE A1 can specify a specific contact IP address, so that the called S-CSCF can only send the invitation message to this IP address Registered user terminal.

411 to 420 are a reverse process of 401 to 410, and the initiator of the capability exchange in this process is the terminal equipment UE B1 of user B. After receiving 417 and 420 200OK, UE B1 saves the terminal capabilities and corresponding IP addresses of user A's terminal equipment UE A1 and UE A2. If user B wants to initiate a CSI service through its terminal UE B1, a specific contact IP address can be specified in the invitation message sent, so that the called S-CSCF can only send the invitation message to the user registered with this IP address terminal.

What Fig. 5 provided is an embodiment of the present invention.

UE A has established a CS domain call with user B's terminal B1. When UE A wants to initiate a terminal capability exchange request to the terminal of user B, UE A sends a query QUERY message 501 to its S-CSCFA, which contains the Request-URI composed of the phone number of terminal B1 of user B or User B's public user identifier PUI. S-CSCF A converts Request-URI into SIP URI in email form. S-CSCF A sends a query QUERY message 502 to S-CSCF B, which includes converted SIP URI and so on. 503S-CSCF B queries the registration information of the user equipment, and knows that the SIP URI corresponds to two IP addresses, which are respectively terminal B1 and terminal B2. Then S-CSCF B returns a response message (3xx or 200 OK) 504 to S-CSCF A, and the message includes the IP address of B1 and the IP address of B2 respectively. S-CSCF A returns the message to UE A505. UE A knows the IP addresses of all terminals of user B, then the subsequent 506 and 507 sent include the IP addresses of B1 and B2, and the SIP URI of user B and other information. After receiving this message, UE B1 and UE B2 include their terminal capabilities in the 200OK message. When UE A receives 508 and 509, it saves the terminal capabilities of UE B1 and UE B2. In the subsequent invitation message, UE A includes the IP address in the message, so that S-CSCF B knows which terminal device to route the invitation message to.

Figure 6 shows another embodiment of the present invention.

Through the methods shown in Figure 4 and Figure 5, UE A has obtained the terminal capabilities of user B's terminal equipment B1 and B2. Next, UE A needs to perform CSI service, add an IMS session, and select UE B2 as the peer end for establishing the IMS session. UE A sends a 601 invitation message to its S-CSCF A, which contains UE B's SIP URI, or TEL URI, UE B2's IP address and other information. S-CSCF A converts the TEL URI into a SIP URI, and forwards the message to S-CSCF B602. S-CSCF B finds that the message contains the IP address of UE B2, so it sends the message only to UE B2603. After UE B2 receives the invitation message, it receives the IMS call and sends 200 OK to UE A. The message is forwarded by 605 and 606 and finally received by UE A.

Claims (9)

1. A method for supporting combined circuit domain calls and Internet multimedia subsystem dialogues, comprising the following steps: A CS domain call is established between user A and user B; The first terminal of user A obtains the capabilities and IP addresses of all terminals of user B; The first terminal of user B obtains the capabilities and IP addresses of all terminals of user A; User A or user B carries the called IP address in the invitation message, and sends the invitation message to the called service call session control function; The called service call session control function sends the message to the called terminal that matches the IP address contained in the invitation message, characterized in that the first terminal of user A obtains the ability of all terminals of user B and IP address includes steps: 1) The first terminal of user A sends a transmission message to the serving call session control function A; 2) The S-CSCF A sends a transmission message to the S-CSCF B; 3) The service call session control function B sends a transmission message to all terminals of the user B with the terminal identified by the SIP URI; 4) The terminal of user B sends a 200OK message to the service call session control function B, and the 200OK message includes the capability and IP address of the user B terminal; 5) SCSCF B forwards all received 200OK messages to SCSCF A; 6) The first terminal of user A saves the received terminal capability and IP address of user B. 2. The method according to claim 1, characterized in that the transmission message of step 1) comprises SIP URI or TEL URI. 3. The method according to claim 1, characterized in that the transmission message of step 2) comprises a SIP URI. 4. The method according to claim 1, characterized in that the transmission message of step 3) comprises a SIP URI. 5. A method for supporting combined circuit domain calls and Internet multimedia subsystem dialogues, comprising the following steps: A CS domain call is established between user A and user B; The first terminal of user A obtains the capabilities and IP addresses of all terminals of user B; The first terminal of user B obtains the capabilities and IP addresses of all terminals of user A; User A or user B carries the called IP address in the invitation message, and sends the invitation message to the called service call session control function; The called service call session control function sends the invitation message to the called terminal matching the IP address contained in the invitation message; It is characterized in that the first terminal of user A obtains the capabilities and IP addresses of all terminals of user B including steps: a) The terminal of user A sends an inquiry message to the service call session control function A; b) the S-CSCF A sends an inquiry message to the S-CSCF B; C) the service call session control function B returns a response message to the service call session control function A, and the response message includes the IP addresses of all terminals of the user B registered with the SIP URI; d) The service call session control function A returns a response message to UE A; e) user A sends an option message to the terminal of user B, and the option message includes the IP address of the terminal of user B; f) The terminal of user B returns 200 OK to the terminal of user A, including the capability of user B's terminal. 6. The method according to claim 5, characterized in that the inquiry message in the step a) comprises SIP URI or TEL URI. 7. The method according to claim 5, characterized in that the inquiry message of the step b) comprises a SIP URI. 8. The method according to claim 5, characterized in that the response message of said step d) includes the IP addresses of the terminals of all users B registered by the SIP URI. 9. The method according to claim 5, characterized in that the option message in said step e) also includes SIP URI or TEL URI.

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